The present invention relates to a proportional solenoid valve unit comprising a casing having a receiving chamber for a valve housing, to which valve housing a solenoid is connected. In the valve housing a piston is slidably arranged which is displacable against the force of a pressure spring by a push rod of the solenoid.
In this known valve unit the valve housing is sealed in the receiving chamber of the casing with sealing rings. Furthermore, the valve housing is provided with a threaded bore at its end face facing the solenoid in which a threaded part of the solenoid is received. The resulting unit comprised of valve housing and solenoid is secured with a sheet metal member and fastened to a casing. In order to prevent damage to the sealing rings of the valve housing during mounting of the unit into the casing, the casing, respectively, its receiving chamber must be provided with insertion slants at the end of the receiving chamber. This leads to additional manufacturing steps during manufacture of the receiving chamber. Furthermore, the valve housing must be provided in complicated manufacturing steps with grooves for insertion of the sealing rings. The threaded bore also requires a difficult and expensive manufacture. Furthermore, securing the unit comprised of valve housing and solenoid with a sheet metal member is complicated, especially in view of the fact that for this purpose an additional component in the form of the sheet metal member and corresponding screws are required. Thus, this proportional solenoid valve unit of the prior art is expensive to manufacture and difficult to assemble.
It is therefore an object of the present invention to improve a proportional solenoid valve unit of the aforementioned kind such that it is comprised of only few components that are preferably standardized components and that can be inexpensively and simply manufactured and mounted.